This letter explores geometrical optics-based raytracing in combination with modal analysis to realize an open cavity structure as an advanced variant of the resonant cavity antenna (RCA). Additional ray confinement has been ensured by determining accurate phase-locking conditions as demonstrated for the first time. Its combination with the analysis of the cavity mode has also been introduced to determine the optimum design parameters, achieving improved radiation properties. With respect to a reference RCA reported earlier, the proposed approach exhibits a remarkable improvement in gain by 4–9 dB, resulting in about 17 dBi peak value consistently over the full 18% matching bandwidth. This is resultant from an increase in aperture efficiency, typically from 27% to 74%. This is achieved without any compromise with the cross-polarization property. The sidelobe level improves over the band except in higher frequency in H-plane. The proposed concept is commercially viable, showing significantly advantageous features.

中文翻译：

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基于几何光学的腔谐振天线的高级设计

这封信探讨了基于几何光学的射线追踪与模态分析的结合，以实现作为谐振腔天线（RCA）的高级变体的开放腔结构。如第一次证明的那样，通过确定精确的锁相条件，可以确保附加的光线约束。还已将其与腔模分析相结合，以确定最佳设计参数，从而实现了改进的辐射性能。相对于先前报道的参考RCA，所提出的方法在增益上显着提高了4–9 dB，从而在整个18％的匹配带宽上始终保持约17 dBi的峰值。这是由于孔径效率通常从27％提高到74％而引起的。这是在不影响交叉极化特性的情况下实现的。旁瓣电平在整个频带上都得到改善，除了在H平面上的频率更高。所提出的概念在商业上是可行的，显示出明显有利的特征。